1. Field of the Invention
The present invention relates to a camera control system that allows a plurality of computer terminals to control video cameras, particularly a monitor camera, through a network.
2. Description of the Related Art
Conventional monitoring systems include a synthesizer for synthesizing analog videos output by a plurality of video cameras with camera direction adjusting capability, and a switcher that switches videos, from the video cameras, presented on monitors. Such a system is typically installed in a relatively small-scale building, and is a localized monitoring system. Newly marketed is a remote monitoring system which offers a dramatically extended transmission line employing a digital network system such as LAN or ISDN, instead of analog cable, as a transmission line for a video signal from a video camera.
The conventional systems further employ a personal computer (PC) in a monitoring terminal to present videos on GUI (Graphical User Interface) so that even an unexperienced user may easily control the system.
In such a system, it may happen that a plurality of users make their own computers display the video from the same video camera at almost the same time, or operate the same video camera from their own computer terminals at almost the same time. When a contention for gaining control of the same video camera takes place, control of the video camera is given to only a single computer terminal. When a certain computer currently has control over the video camera, the system must perform a complex process, such as a request queueing process or exclusive control process, with another computer terminal requesting control over the video camera.
Client terminals are not notified of information about control acquisition status for the video camera, and if the clients failed to gain control, they are unable to know whey they did.
Accordingly, it is an object of the present invention to provide a camera control system that notifies a client""s computer terminal of the locality of control of a video camera to help a user easily know the status of the video camera.
According to one aspect of the present invention, the client terminal for controlling a video camera by gaining control of the video camera includes an output unit for outputting, to a video sending terminal, a request for the control of the video camera, and a notifying unit for notifying another client terminal, which currently has the control of the video camera, that the output unit has issued the request for the control of the video camera to the video sending terminal.
According to another aspect of the present invention, the video sending terminal for sending to client terminals a video from a video camera through a network and controlling the video camera in accordance with a control command from a client terminal, includes a control unit for controlling the video camera in accordance with the control command of the video camera, and a notifying unit for notifying a first client terminal that a control command of the video camera has been newly received from a second client terminal, when the control command has been newly received from the second client terminal different from the first client terminal which has issued the control command under which the control means currently controls the video camera.
According to yet another aspect of the present invention, the client terminal for controlling a video camera by issuing a control command to a video sending terminal, includes an output unit for outputting the control command for the video camera to the video sending terminal, and a notifying unit for notifying another client terminal, which currently controls the video camera, that a control command for the video camera has been issued to the video sending terminal.
According to yet another aspect of the present invention, the client terminal for controlling a plurality of video cameras through a network, includes a display unit for selectively displaying videos from the plurality of video cameras on the same screen, and a retrieving unit for retrieving the information about the user of another client terminal, if the other client terminal receives any video, among the videos from the plurality of video cameras, presented in the display unit, wherein, for displaying, the display unit superimposes the information about the user of the client terminal retrieved by the retrieving unit onto the video which the another client terminal also receives from the video camera.
According to yet another aspect of the present invention, the control method for a camera control system, in which a client terminal having control controls a video camera connected to a video sending terminal, includes the steps of outputting a request for the control of the video camera to the video sending terminal, receiving the request for the control of the video camera output in the outputting step, issuing the control of the video camera in response to the request for the control of the video camera received in the receiving step, and notifying the client terminal, which currently has the control of the video camera, that another client terminal has newly made a request for the control of the video camera, when the request for the control of the video camera has newly been made by the other client terminal.
According to yet another aspect of the present invention, the control method for a camera control system, in which a client terminal controls a video camera by sending a control command to a video sending terminal, includes the steps of outputting the control command of the video camera to the video sending terminal, controlling the video camera in accordance with the control command of the video camera output in the outputting step, and notifying a first client terminal that a control command of the video camera has been newly received from a second client terminal, when the control command has been newly received from the second client terminal different from the first client terminal which has issued the control command under which the control step currently controls the video camera.
According to yet another aspect of the present invention, the camera control method, in which a client terminal controls a plurality of video cameras by issuing a control command through a network, includes the steps of selectively displaying videos from the plurality of video cameras on the same screen, and retrieving the information about the user of another client terminal, if the other client terminal receives any video, among the videos from the plurality of video cameras, presented in the displaying step, wherein, for displaying, the displaying step superimposes the information about the user of the other client terminal retrieved in the retrieving step onto the video which the other client terminal also receives from the video camera.
According to yet another aspect of the present invention, the storage medium stores a program that is executed by a video sending terminal that controls a video camera in accordance with a control command from a client terminal having the control of the video camera, and the program includes the steps of issuing the control of the video camera in response to a request for the control of the video camera output by the client terminal, and notifying the client terminal, which currently has the control of the video camera, that the request for the control of the video camera has been newly issued, when the request for the control of the video camera has been newly issued with the video camera under control.
According to yet another aspect of the present invention, the storage medium stores a program that is executed by a client terminal that controls a video camera by gaining control, and the program includes the steps of outputting a request for the control of a video camera to a video sending terminal, and notifying another client terminal, which has currently the control of the video camera, that the request for the control of the video camera has been issued to the video sending terminal, when the other client terminal currently has the control of the video camera.
According to yet another aspect of the present invention, the storage medium stores a program that is executed by a video sending terminal that sends a video from a video camera to a client terminal through a network and controls the video camera in accordance with a control command from the client terminal. The program includes the steps of controlling the video camera in accordance with the control command of the video camera, and notifying a first client terminal that a control command of the video camera has been newly received from a second client terminal, when the control command has been newly received from the second client terminal different from the first client terminal which has issued the control command under which the video camera is currently controlled.
According to yet another aspect of the present invention, the storage medium stores a program that is executed by a client terminal that controls a video camera by outputting a control command to a video sending terminal, and the program includes the steps of outputting the control command of the video camera to the video sending terminal, and notifying another client terminal, which currently controls the video camera, that a control command of the video camera has been output to the video sending terminal, when the video camera is controlled by the other client terminal.
According to yet another aspect of the present invention, the storage medium stores a program that is executed by a client terminal that controls a plurality of video cameras through a network, and the program includes the steps of selectively displaying videos from the plurality of video cameras on the same screen, and retrieving the information about the user of another client terminal, if the other client terminal receives any video, among the videos from the plurality of video cameras, presented in the displaying step, wherein, when displayed, the information about the user of the other client terminal retrieved is superimposed onto the video which the other client terminal also receives from the video camera.
These and other objects and features of the present invention will become apparent from the following description and the accompanying drawings.